Abstract: The relations of welding method, welding procedure with weld mechanical properties are lack of deep understanding. Based on experiment results, the characteristics of weld partition, weld metallurgy and mechanical properties of the joint were summarized. For welding of aluminum alloy, welding passes sequence, preheating temperature, welding torch oscillation, groove angle, etc, are critical factors of welding procedure which have significant influence on mechanical properties of the joint. The design of whole product should be resolved to the welded joint design, being considerate to complex service loads and environment. The scientific original design of welded structure is based on the adequate experiment data of material, environment, fatigue.